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<li class="navelem"><a class="el" href="namespacebadgerdb.html">badgerdb</a></li><li class="navelem"><a class="el" href="classbadgerdb_1_1_file.html">File</a></li>  </ul>
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<div class="header">
  <div class="summary">
<a href="#pub-methods">Public Member Functions</a> &#124;
<a href="#pub-static-methods">Static Public Member Functions</a> &#124;
<a href="#friends">Friends</a> &#124;
<a href="classbadgerdb_1_1_file-members.html">List of all members</a>  </div>
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<div class="title">badgerdb::File Class Reference</div>  </div>
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<p>Class which represents a file in the filesystem containing database pages.  
 <a href="classbadgerdb_1_1_file.html#details">More...</a></p>

<p><code>#include &lt;<a class="el" href="file_8h_source.html">file.h</a>&gt;</code></p>
<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr class="memitem:a600baaf77d18f39e51ae7473eca633c4"><td class="memItemLeft" align="right" valign="top">&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a600baaf77d18f39e51ae7473eca633c4">File</a> (const <a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp;other)</td></tr>
<tr class="separator:a600baaf77d18f39e51ae7473eca633c4"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ac403c631aec085e9f12992f260a57155"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#ac403c631aec085e9f12992f260a57155">operator=</a> (const <a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp;rhs)</td></tr>
<tr class="separator:ac403c631aec085e9f12992f260a57155"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a97fd6e3ae8dd11be883289b69d560287"><td class="memItemLeft" align="right" valign="top">&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a97fd6e3ae8dd11be883289b69d560287">~File</a> ()</td></tr>
<tr class="separator:a97fd6e3ae8dd11be883289b69d560287"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a7d0e047bcc8dc4cee36aac5b2060bbe3"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classbadgerdb_1_1_page.html">Page</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a7d0e047bcc8dc4cee36aac5b2060bbe3">allocatePage</a> ()</td></tr>
<tr class="separator:a7d0e047bcc8dc4cee36aac5b2060bbe3"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a343b7fb1a238992f02454e9e81837acd"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classbadgerdb_1_1_page.html">Page</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a343b7fb1a238992f02454e9e81837acd">readPage</a> (const <a class="el" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a> page_number) const</td></tr>
<tr class="separator:a343b7fb1a238992f02454e9e81837acd"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a9a1b3cc43c4631bde58c1c4f670e1036"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a> (const <a class="el" href="classbadgerdb_1_1_page.html">Page</a> &amp;new_page)</td></tr>
<tr class="separator:a9a1b3cc43c4631bde58c1c4f670e1036"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a829a68ccfbeb0c9f66f3a2db7e0b99fe"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a829a68ccfbeb0c9f66f3a2db7e0b99fe">deletePage</a> (const <a class="el" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a> page_number)</td></tr>
<tr class="separator:a829a68ccfbeb0c9f66f3a2db7e0b99fe"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:af16040a60f18c99305348077ac9e8aa8"><td class="memItemLeft" align="right" valign="top">const std::string &amp;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a> () const</td></tr>
<tr class="separator:af16040a60f18c99305348077ac9e8aa8"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a32e94f392eb3740dd9eb9101b9e09d47"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classbadgerdb_1_1_file_iterator.html">FileIterator</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a32e94f392eb3740dd9eb9101b9e09d47">begin</a> ()</td></tr>
<tr class="separator:a32e94f392eb3740dd9eb9101b9e09d47"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a01e224676a67634f21d53fc4189b8f11"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classbadgerdb_1_1_file_iterator.html">FileIterator</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a01e224676a67634f21d53fc4189b8f11">end</a> ()</td></tr>
<tr class="separator:a01e224676a67634f21d53fc4189b8f11"><td class="memSeparator" colspan="2">&#160;</td></tr>
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<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-static-methods"></a>
Static Public Member Functions</h2></td></tr>
<tr class="memitem:a1fb708b45103a606f189850d6bf83a0c"><td class="memItemLeft" align="right" valign="top">static <a class="el" href="classbadgerdb_1_1_file.html">File</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a1fb708b45103a606f189850d6bf83a0c">create</a> (const std::string &amp;<a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)</td></tr>
<tr class="separator:a1fb708b45103a606f189850d6bf83a0c"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a8462afdbd250c0a483ddfbde144c8732"><td class="memItemLeft" align="right" valign="top">static <a class="el" href="classbadgerdb_1_1_file.html">File</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a8462afdbd250c0a483ddfbde144c8732">open</a> (const std::string &amp;<a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)</td></tr>
<tr class="separator:a8462afdbd250c0a483ddfbde144c8732"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a1cc69467366badbd68021ac76a91190e"><td class="memItemLeft" align="right" valign="top">static void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a1cc69467366badbd68021ac76a91190e">remove</a> (const std::string &amp;<a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)</td></tr>
<tr class="separator:a1cc69467366badbd68021ac76a91190e"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a64836156a9bb5f81d2c2c4e6f3ada24d"><td class="memItemLeft" align="right" valign="top">static bool&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a64836156a9bb5f81d2c2c4e6f3ada24d">isOpen</a> (const std::string &amp;<a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)</td></tr>
<tr class="separator:a64836156a9bb5f81d2c2c4e6f3ada24d"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a864d59b12302c26b14967bd1d3e520bd"><td class="memItemLeft" align="right" valign="top">static bool&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="classbadgerdb_1_1_file.html#a864d59b12302c26b14967bd1d3e520bd">exists</a> (const std::string &amp;<a class="el" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)</td></tr>
<tr class="separator:a864d59b12302c26b14967bd1d3e520bd"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table><table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="friends"></a>
Friends</h2></td></tr>
<tr class="memitem:a3cd56c83d638b63a676ae3c4b51dc1b2"><td class="memItemLeft" align="right" valign="top"><a id="a3cd56c83d638b63a676ae3c4b51dc1b2"></a>
class&#160;</td><td class="memItemRight" valign="bottom"><b>FileIterator</b></td></tr>
<tr class="separator:a3cd56c83d638b63a676ae3c4b51dc1b2"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a400f700afa1fdf03ca18d08ab8ade7f7"><td class="memItemLeft" align="right" valign="top"><a id="a400f700afa1fdf03ca18d08ab8ade7f7"></a>
class&#160;</td><td class="memItemRight" valign="bottom"><b>FileTest</b></td></tr>
<tr class="separator:a400f700afa1fdf03ca18d08ab8ade7f7"><td class="memSeparator" colspan="2">&#160;</td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>Class which represents a file in the filesystem containing database pages. </p>
<p>The <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> class wraps a stream to an underlying file on disk. Files contain fixed-sized pages, and they never deallocate space (though they do reuse deleted pages if possible). If multiple <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> objects refer to the same underlying file, they will share the stream in memory. If a file that has already been opened (possibly by another query), then the <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> class detects this (by looking in the open_streams_ map) and just returns a file object with the already created stream for the file without actually opening the UNIX file again.</p>
<dl class="section warning"><dt>Warning</dt><dd>This class is not threadsafe. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8h_source.html#l00073">73</a> of file <a class="el" href="file_8h_source.html">file.h</a>.</p>
</div><h2 class="groupheader">Constructor &amp; Destructor Documentation</h2>
<a id="a600baaf77d18f39e51ae7473eca633c4"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a600baaf77d18f39e51ae7473eca633c4">&#9670;&nbsp;</a></span>File()</h2>

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          <td class="memname">badgerdb::File::File </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp;&#160;</td>
          <td class="paramname"><em>other</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Copy constructor.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">other</td><td><a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object to copy. </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>A copy of the <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00065">65</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;  : filename_(other.filename_),</div>
<div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;    stream_(open_streams_[filename_]) {</div>
<div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;  ++open_counts_[filename_];</div>
<div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;}</div>
</div><!-- fragment -->
</div>
</div>
<a id="a97fd6e3ae8dd11be883289b69d560287"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a97fd6e3ae8dd11be883289b69d560287">&#9670;&nbsp;</a></span>~File()</h2>

<div class="memitem">
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      <table class="memname">
        <tr>
          <td class="memname">badgerdb::File::~File </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Destructor that automatically closes the underlying file if no other <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> objects are using it. </p>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00080">80</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;            {</div>
<div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;  close();</div>
<div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;}</div>
</div><!-- fragment -->
</div>
</div>
<h2 class="groupheader">Member Function Documentation</h2>
<a id="a7d0e047bcc8dc4cee36aac5b2060bbe3"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a7d0e047bcc8dc4cee36aac5b2060bbe3">&#9670;&nbsp;</a></span>allocatePage()</h2>

<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname"><a class="el" href="classbadgerdb_1_1_page.html">Page</a> badgerdb::File::allocatePage </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Allocates a new page in the file.</p>
<dl class="section return"><dt>Returns</dt><dd>The new page. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00084">84</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;                        {</div>
<div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;  FileHeader header = readHeader();</div>
<div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;  Page new_page;</div>
<div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;  Page existing_page;</div>
<div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;  <span class="keywordflow">if</span> (header.num_free_pages &gt; 0) {</div>
<div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;    new_page = <a class="code" href="classbadgerdb_1_1_file.html#a343b7fb1a238992f02454e9e81837acd">readPage</a>(header.first_free_page, <span class="keyword">true</span> <span class="comment">/* allow_free */</span>);</div>
<div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;    new_page.set_page_number(header.first_free_page);</div>
<div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;    header.first_free_page = new_page.next_page_number();</div>
<div class="line"><a name="l00092"></a><span class="lineno">   92</span>&#160;    --header.num_free_pages;</div>
<div class="line"><a name="l00093"></a><span class="lineno">   93</span>&#160; </div>
<div class="line"><a name="l00094"></a><span class="lineno">   94</span>&#160;    <span class="keywordflow">if</span> (header.first_used_page == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a> ||</div>
<div class="line"><a name="l00095"></a><span class="lineno">   95</span>&#160;        header.first_used_page &gt; new_page.page_number()) {</div>
<div class="line"><a name="l00096"></a><span class="lineno">   96</span>&#160;      <span class="comment">// Either have no pages used or the head of the used list is a page later</span></div>
<div class="line"><a name="l00097"></a><span class="lineno">   97</span>&#160;      <span class="comment">// than the one we just allocated, so add the new page to the head.</span></div>
<div class="line"><a name="l00098"></a><span class="lineno">   98</span>&#160;      <span class="keywordflow">if</span> (header.first_used_page &gt; new_page.page_number()) {</div>
<div class="line"><a name="l00099"></a><span class="lineno">   99</span>&#160;        new_page.set_next_page_number(header.first_used_page);</div>
<div class="line"><a name="l00100"></a><span class="lineno">  100</span>&#160;      }</div>
<div class="line"><a name="l00101"></a><span class="lineno">  101</span>&#160;      header.first_used_page = new_page.page_number();</div>
<div class="line"><a name="l00102"></a><span class="lineno">  102</span>&#160;    } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00103"></a><span class="lineno">  103</span>&#160;      <span class="comment">// New page is reused from somewhere after the beginning, so we need to</span></div>
<div class="line"><a name="l00104"></a><span class="lineno">  104</span>&#160;      <span class="comment">// find where in the used list to insert it.</span></div>
<div class="line"><a name="l00105"></a><span class="lineno">  105</span>&#160;      <a class="code" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a> next_page_number = <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>;</div>
<div class="line"><a name="l00106"></a><span class="lineno">  106</span>&#160;      <span class="keywordflow">for</span> (FileIterator iter = <a class="code" href="classbadgerdb_1_1_file.html#a32e94f392eb3740dd9eb9101b9e09d47">begin</a>(); iter != <a class="code" href="classbadgerdb_1_1_file.html#a01e224676a67634f21d53fc4189b8f11">end</a>(); ++iter) {</div>
<div class="line"><a name="l00107"></a><span class="lineno">  107</span>&#160;        next_page_number = (*iter).next_page_number();</div>
<div class="line"><a name="l00108"></a><span class="lineno">  108</span>&#160;        <span class="keywordflow">if</span> (next_page_number &gt; new_page.page_number() ||</div>
<div class="line"><a name="l00109"></a><span class="lineno">  109</span>&#160;            next_page_number == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>) {</div>
<div class="line"><a name="l00110"></a><span class="lineno">  110</span>&#160;          existing_page = *iter;</div>
<div class="line"><a name="l00111"></a><span class="lineno">  111</span>&#160;          <span class="keywordflow">break</span>;</div>
<div class="line"><a name="l00112"></a><span class="lineno">  112</span>&#160;        }</div>
<div class="line"><a name="l00113"></a><span class="lineno">  113</span>&#160;      }</div>
<div class="line"><a name="l00114"></a><span class="lineno">  114</span>&#160;      existing_page.set_next_page_number(new_page.page_number());</div>
<div class="line"><a name="l00115"></a><span class="lineno">  115</span>&#160;      new_page.set_next_page_number(next_page_number);</div>
<div class="line"><a name="l00116"></a><span class="lineno">  116</span>&#160;    }</div>
<div class="line"><a name="l00117"></a><span class="lineno">  117</span>&#160; </div>
<div class="line"><a name="l00118"></a><span class="lineno">  118</span>&#160;    assert((header.num_free_pages == 0) ==</div>
<div class="line"><a name="l00119"></a><span class="lineno">  119</span>&#160;           (header.first_free_page == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>));</div>
<div class="line"><a name="l00120"></a><span class="lineno">  120</span>&#160;  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00121"></a><span class="lineno">  121</span>&#160;    new_page.set_page_number(header.num_pages);</div>
<div class="line"><a name="l00122"></a><span class="lineno">  122</span>&#160;    <span class="keywordflow">if</span> (header.first_used_page == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>) {</div>
<div class="line"><a name="l00123"></a><span class="lineno">  123</span>&#160;      header.first_used_page = new_page.page_number();</div>
<div class="line"><a name="l00124"></a><span class="lineno">  124</span>&#160;    } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00125"></a><span class="lineno">  125</span>&#160;      <span class="comment">// If we have pages allocated, we need to add the new page to the tail</span></div>
<div class="line"><a name="l00126"></a><span class="lineno">  126</span>&#160;      <span class="comment">// of the linked list.</span></div>
<div class="line"><a name="l00127"></a><span class="lineno">  127</span>&#160;      <span class="keywordflow">for</span> (FileIterator iter = <a class="code" href="classbadgerdb_1_1_file.html#a32e94f392eb3740dd9eb9101b9e09d47">begin</a>(); iter != <a class="code" href="classbadgerdb_1_1_file.html#a01e224676a67634f21d53fc4189b8f11">end</a>(); ++iter) {</div>
<div class="line"><a name="l00128"></a><span class="lineno">  128</span>&#160;        <span class="keywordflow">if</span> ((*iter).next_page_number() == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>) {</div>
<div class="line"><a name="l00129"></a><span class="lineno">  129</span>&#160;          existing_page = *iter;</div>
<div class="line"><a name="l00130"></a><span class="lineno">  130</span>&#160;          <span class="keywordflow">break</span>;</div>
<div class="line"><a name="l00131"></a><span class="lineno">  131</span>&#160;        }</div>
<div class="line"><a name="l00132"></a><span class="lineno">  132</span>&#160;      }</div>
<div class="line"><a name="l00133"></a><span class="lineno">  133</span>&#160;      assert(existing_page.isUsed());</div>
<div class="line"><a name="l00134"></a><span class="lineno">  134</span>&#160;      existing_page.set_next_page_number(new_page.page_number());</div>
<div class="line"><a name="l00135"></a><span class="lineno">  135</span>&#160;    }</div>
<div class="line"><a name="l00136"></a><span class="lineno">  136</span>&#160;    ++header.num_pages;</div>
<div class="line"><a name="l00137"></a><span class="lineno">  137</span>&#160;  }</div>
<div class="line"><a name="l00138"></a><span class="lineno">  138</span>&#160;  <a class="code" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a>(new_page.page_number(), new_page);</div>
<div class="line"><a name="l00139"></a><span class="lineno">  139</span>&#160;  <span class="keywordflow">if</span> (existing_page.page_number() != <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>) {</div>
<div class="line"><a name="l00140"></a><span class="lineno">  140</span>&#160;    <span class="comment">// If we updated an existing page by inserting the new page into the</span></div>
<div class="line"><a name="l00141"></a><span class="lineno">  141</span>&#160;    <span class="comment">// used list, we need to write it out.</span></div>
<div class="line"><a name="l00142"></a><span class="lineno">  142</span>&#160;    <a class="code" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a>(existing_page.page_number(), existing_page);</div>
<div class="line"><a name="l00143"></a><span class="lineno">  143</span>&#160;  }</div>
<div class="line"><a name="l00144"></a><span class="lineno">  144</span>&#160;  writeHeader(header);</div>
<div class="line"><a name="l00145"></a><span class="lineno">  145</span>&#160; </div>
<div class="line"><a name="l00146"></a><span class="lineno">  146</span>&#160;  <span class="keywordflow">return</span> new_page;</div>
<div class="line"><a name="l00147"></a><span class="lineno">  147</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a32e94f392eb3740dd9eb9101b9e09d47">&#9670;&nbsp;</a></span>begin()</h2>

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          <td class="memname"><a class="el" href="classbadgerdb_1_1_file_iterator.html">FileIterator</a> badgerdb::File::begin </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Returns an iterator at the first page in the file.</p>
<dl class="section return"><dt>Returns</dt><dd>Iterator at first page of file. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00214">214</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00214"></a><span class="lineno">  214</span>&#160;                         {</div>
<div class="line"><a name="l00215"></a><span class="lineno">  215</span>&#160;  <span class="keyword">const</span> FileHeader&amp; header = readHeader();</div>
<div class="line"><a name="l00216"></a><span class="lineno">  216</span>&#160;  <span class="keywordflow">return</span> FileIterator(<span class="keyword">this</span>, header.first_used_page);</div>
<div class="line"><a name="l00217"></a><span class="lineno">  217</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a1fb708b45103a606f189850d6bf83a0c">&#9670;&nbsp;</a></span>create()</h2>

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          <td class="memname"><a class="el" href="classbadgerdb_1_1_file.html">File</a> badgerdb::File::create </td>
          <td>(</td>
          <td class="paramtype">const std::string &amp;&#160;</td>
          <td class="paramname"><em>filename</em></td><td>)</td>
          <td></td>
        </tr>
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  <td class="mlabels-right">
<span class="mlabels"><span class="mlabel">static</span></span>  </td>
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<p>Creates a new file.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">filename</td><td>Name of the file. </td></tr>
  </table>
  </dd>
</dl>
<dl class="exception"><dt>Exceptions</dt><dd>
  <table class="exception">
    <tr><td class="paramname"><a class="el" href="classbadgerdb_1_1_file_exists_exception.html" title="An exception that is thrown when a file creation is requested for a filename that already exists.">FileExistsException</a></td><td>If the requested file already exists. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00029">29</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;                                           {</div>
<div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;  <span class="keywordflow">return</span> <a class="code" href="classbadgerdb_1_1_file.html#a600baaf77d18f39e51ae7473eca633c4">File</a>(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>, <span class="keyword">true</span> <span class="comment">/* create_new */</span>);</div>
<div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a829a68ccfbeb0c9f66f3a2db7e0b99fe">&#9670;&nbsp;</a></span>deletePage()</h2>

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      <table class="memname">
        <tr>
          <td class="memname">void badgerdb::File::deletePage </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a>&#160;</td>
          <td class="paramname"><em>page_number</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Deletes a page from the file.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">page_number</td><td>Number of page to delete. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00184">184</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00184"></a><span class="lineno">  184</span>&#160;                                              {</div>
<div class="line"><a name="l00185"></a><span class="lineno">  185</span>&#160;  FileHeader header = readHeader();</div>
<div class="line"><a name="l00186"></a><span class="lineno">  186</span>&#160;  Page existing_page = <a class="code" href="classbadgerdb_1_1_file.html#a343b7fb1a238992f02454e9e81837acd">readPage</a>(page_number);</div>
<div class="line"><a name="l00187"></a><span class="lineno">  187</span>&#160;  Page previous_page;</div>
<div class="line"><a name="l00188"></a><span class="lineno">  188</span>&#160;  <span class="comment">// If this page is the head of the used list, update the header to point to</span></div>
<div class="line"><a name="l00189"></a><span class="lineno">  189</span>&#160;  <span class="comment">// the next page in line.</span></div>
<div class="line"><a name="l00190"></a><span class="lineno">  190</span>&#160;  <span class="keywordflow">if</span> (page_number == header.first_used_page) {</div>
<div class="line"><a name="l00191"></a><span class="lineno">  191</span>&#160;    header.first_used_page = existing_page.next_page_number();</div>
<div class="line"><a name="l00192"></a><span class="lineno">  192</span>&#160;  } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00193"></a><span class="lineno">  193</span>&#160;    <span class="comment">// Walk the used list so we can update the page that points to this one.</span></div>
<div class="line"><a name="l00194"></a><span class="lineno">  194</span>&#160;    <span class="keywordflow">for</span> (FileIterator iter = <a class="code" href="classbadgerdb_1_1_file.html#a32e94f392eb3740dd9eb9101b9e09d47">begin</a>(); iter != <a class="code" href="classbadgerdb_1_1_file.html#a01e224676a67634f21d53fc4189b8f11">end</a>(); ++iter) {</div>
<div class="line"><a name="l00195"></a><span class="lineno">  195</span>&#160;      previous_page = *iter;</div>
<div class="line"><a name="l00196"></a><span class="lineno">  196</span>&#160;      <span class="keywordflow">if</span> (previous_page.next_page_number() == existing_page.page_number()) {</div>
<div class="line"><a name="l00197"></a><span class="lineno">  197</span>&#160;        previous_page.set_next_page_number(existing_page.next_page_number());</div>
<div class="line"><a name="l00198"></a><span class="lineno">  198</span>&#160;        <span class="keywordflow">break</span>;</div>
<div class="line"><a name="l00199"></a><span class="lineno">  199</span>&#160;      }</div>
<div class="line"><a name="l00200"></a><span class="lineno">  200</span>&#160;    }</div>
<div class="line"><a name="l00201"></a><span class="lineno">  201</span>&#160;  }</div>
<div class="line"><a name="l00202"></a><span class="lineno">  202</span>&#160;  <span class="comment">// Clear the page and add it to the head of the free list.</span></div>
<div class="line"><a name="l00203"></a><span class="lineno">  203</span>&#160;  existing_page.initialize();</div>
<div class="line"><a name="l00204"></a><span class="lineno">  204</span>&#160;  existing_page.set_next_page_number(header.first_free_page);</div>
<div class="line"><a name="l00205"></a><span class="lineno">  205</span>&#160;  header.first_free_page = page_number;</div>
<div class="line"><a name="l00206"></a><span class="lineno">  206</span>&#160;  ++header.num_free_pages;</div>
<div class="line"><a name="l00207"></a><span class="lineno">  207</span>&#160;  <span class="keywordflow">if</span> (previous_page.isUsed()) {</div>
<div class="line"><a name="l00208"></a><span class="lineno">  208</span>&#160;    <a class="code" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a>(previous_page.page_number(), previous_page);</div>
<div class="line"><a name="l00209"></a><span class="lineno">  209</span>&#160;  }</div>
<div class="line"><a name="l00210"></a><span class="lineno">  210</span>&#160;  <a class="code" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a>(page_number, existing_page);</div>
<div class="line"><a name="l00211"></a><span class="lineno">  211</span>&#160;  writeHeader(header);</div>
<div class="line"><a name="l00212"></a><span class="lineno">  212</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a01e224676a67634f21d53fc4189b8f11">&#9670;&nbsp;</a></span>end()</h2>

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          <td class="memname"><a class="el" href="classbadgerdb_1_1_file_iterator.html">FileIterator</a> badgerdb::File::end </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td></td>
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<p>Returns an iterator representing the page after the last page in the file. This iterator should not be dereferenced.</p>
<dl class="section return"><dt>Returns</dt><dd>Iterator representing page after the last page in the file. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00219">219</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00219"></a><span class="lineno">  219</span>&#160;                       {</div>
<div class="line"><a name="l00220"></a><span class="lineno">  220</span>&#160;  <span class="keywordflow">return</span> FileIterator(<span class="keyword">this</span>, <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>);</div>
<div class="line"><a name="l00221"></a><span class="lineno">  221</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a864d59b12302c26b14967bd1d3e520bd">&#9670;&nbsp;</a></span>exists()</h2>

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          <td class="memname">bool badgerdb::File::exists </td>
          <td>(</td>
          <td class="paramtype">const std::string &amp;&#160;</td>
          <td class="paramname"><em>filename</em></td><td>)</td>
          <td></td>
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<p>Returns true if the file exists and is open.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">filename</td><td>Name of the file. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00054">54</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;                                           {</div>
<div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;  std::fstream file(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>);</div>
<div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;  <span class="keywordflow">if</span>(file)</div>
<div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;  {</div>
<div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;    file.close();</div>
<div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;    <span class="keywordflow">return</span> <span class="keyword">true</span>;</div>
<div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;  }</div>
<div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160; </div>
<div class="line"><a name="l00062"></a><span class="lineno">   62</span>&#160;  <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
<div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#af16040a60f18c99305348077ac9e8aa8">&#9670;&nbsp;</a></span>filename()</h2>

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          <td class="memname">const std::string&amp; badgerdb::File::filename </td>
          <td>(</td>
          <td class="paramname"></td><td>)</td>
          <td> const</td>
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<p>Returns the name of the file this object represents.</p>
<dl class="section return"><dt>Returns</dt><dd>Name of file. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8h_source.html#l00179">179</a> of file <a class="el" href="file_8h_source.html">file.h</a>.</p>
<div class="fragment"><div class="line"><a name="l00179"></a><span class="lineno">  179</span>&#160;{ <span class="keywordflow">return</span> filename_; }</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a64836156a9bb5f81d2c2c4e6f3ada24d">&#9670;&nbsp;</a></span>isOpen()</h2>

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          <td>(</td>
          <td class="paramtype">const std::string &amp;&#160;</td>
          <td class="paramname"><em>filename</em></td><td>)</td>
          <td></td>
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<p>Returns true if the file exists and is open.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">filename</td><td>Name of the file. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00047">47</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;                                           {</div>
<div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;  <span class="keywordflow">if</span> (!<a class="code" href="classbadgerdb_1_1_file.html#a864d59b12302c26b14967bd1d3e520bd">exists</a>(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)) {</div>
<div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;    <span class="keywordflow">return</span> <span class="keyword">false</span>;</div>
<div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;  }</div>
<div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;  <span class="keywordflow">return</span> open_counts_.find(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>) != open_counts_.end();</div>
<div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a8462afdbd250c0a483ddfbde144c8732">&#9670;&nbsp;</a></span>open()</h2>

<div class="memitem">
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          <td class="memname"><a class="el" href="classbadgerdb_1_1_file.html">File</a> badgerdb::File::open </td>
          <td>(</td>
          <td class="paramtype">const std::string &amp;&#160;</td>
          <td class="paramname"><em>filename</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
  </td>
  <td class="mlabels-right">
<span class="mlabels"><span class="mlabel">static</span></span>  </td>
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</div><div class="memdoc">
<p>Opens the file named fileName and returns the corresponding <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object. It first checks if the file is already open. If so, then the new <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object created uses the same input-output stream to read to or write fom that already open file. Reference count (open_counts_ static variable inside the <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object) is incremented whenever an already open file is opened again. Otherwise the UNIX file is actually opened. The fileName and the stream associated with this <a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object are inserted into the open_streams_ map.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">filename</td><td>Name of the file. </td></tr>
  </table>
  </dd>
</dl>
<dl class="exception"><dt>Exceptions</dt><dd>
  <table class="exception">
    <tr><td class="paramname"><a class="el" href="classbadgerdb_1_1_file_not_found_exception.html" title="An exception that is thrown when a file operation is requested for a filename that doesn&#39;t exist.">FileNotFoundException</a></td><td>If the requested file doesn't exist. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00033">33</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;                                         {</div>
<div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;  <span class="keywordflow">return</span> <a class="code" href="classbadgerdb_1_1_file.html#a600baaf77d18f39e51ae7473eca633c4">File</a>(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>, <span class="keyword">false</span> <span class="comment">/* create_new */</span>);</div>
<div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#ac403c631aec085e9f12992f260a57155">&#9670;&nbsp;</a></span>operator=()</h2>

<div class="memitem">
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      <table class="memname">
        <tr>
          <td class="memname"><a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp; badgerdb::File::operator= </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="classbadgerdb_1_1_file.html">File</a> &amp;&#160;</td>
          <td class="paramname"><em>rhs</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Assignment operator.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">rhs</td><td><a class="el" href="classbadgerdb_1_1_file.html" title="Class which represents a file in the filesystem containing database pages.">File</a> object to assign. </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>Newly assigned file object. </dd></dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00071">71</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;                                     {</div>
<div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;  <span class="comment">// This accounts for self-assignment and assignment of a File object for the</span></div>
<div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;  <span class="comment">// same file.</span></div>
<div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;  close();  <span class="comment">//close my file and associate me with the new one</span></div>
<div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;  filename_ = rhs.filename_;</div>
<div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;  openIfNeeded(<span class="keyword">false</span> <span class="comment">/* create_new */</span>);</div>
<div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;  <span class="keywordflow">return</span> *<span class="keyword">this</span>;</div>
<div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a343b7fb1a238992f02454e9e81837acd">&#9670;&nbsp;</a></span>readPage()</h2>

<div class="memitem">
<div class="memproto">
      <table class="memname">
        <tr>
          <td class="memname"><a class="el" href="classbadgerdb_1_1_page.html">Page</a> badgerdb::File::readPage </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a>&#160;</td>
          <td class="paramname"><em>page_number</em></td><td>)</td>
          <td> const</td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Reads an existing page from the file.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">page_number</td><td>Number of page to read. </td></tr>
  </table>
  </dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>The page. </dd></dl>
<dl class="exception"><dt>Exceptions</dt><dd>
  <table class="exception">
    <tr><td class="paramname"><a class="el" href="classbadgerdb_1_1_invalid_page_exception.html" title="An exception that is thrown when an attempt is made to access an invalid page in a file.">InvalidPageException</a></td><td>If the page doesn't exist in the file or is not currently used. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00149">149</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00149"></a><span class="lineno">  149</span>&#160;                                                  {</div>
<div class="line"><a name="l00150"></a><span class="lineno">  150</span>&#160;  FileHeader header = readHeader();</div>
<div class="line"><a name="l00151"></a><span class="lineno">  151</span>&#160;  <span class="keywordflow">if</span> (page_number &gt;= header.num_pages) {</div>
<div class="line"><a name="l00152"></a><span class="lineno">  152</span>&#160;    <span class="keywordflow">throw</span> InvalidPageException(page_number, filename_);</div>
<div class="line"><a name="l00153"></a><span class="lineno">  153</span>&#160;  }</div>
<div class="line"><a name="l00154"></a><span class="lineno">  154</span>&#160;  <span class="keywordflow">return</span> <a class="code" href="classbadgerdb_1_1_file.html#a343b7fb1a238992f02454e9e81837acd">readPage</a>(page_number, <span class="keyword">false</span> <span class="comment">/* allow_free */</span>);</div>
<div class="line"><a name="l00155"></a><span class="lineno">  155</span>&#160;}</div>
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<a id="a1cc69467366badbd68021ac76a91190e"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a1cc69467366badbd68021ac76a91190e">&#9670;&nbsp;</a></span>remove()</h2>

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  <td class="mlabels-left">
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          <td class="memname">void badgerdb::File::remove </td>
          <td>(</td>
          <td class="paramtype">const std::string &amp;&#160;</td>
          <td class="paramname"><em>filename</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
  </td>
  <td class="mlabels-right">
<span class="mlabels"><span class="mlabel">static</span></span>  </td>
  </tr>
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<p>Deletes an existing file.</p>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">filename</td><td>Name of the file. </td></tr>
  </table>
  </dd>
</dl>
<dl class="exception"><dt>Exceptions</dt><dd>
  <table class="exception">
    <tr><td class="paramname"><a class="el" href="classbadgerdb_1_1_file_not_found_exception.html" title="An exception that is thrown when a file operation is requested for a filename that doesn&#39;t exist.">FileNotFoundException</a></td><td>If the file doesn't exist. </td></tr>
    <tr><td class="paramname"><a class="el" href="classbadgerdb_1_1_file_open_exception.html" title="An exception that is thrown when a file deletion is requested for a filename that&#39;s currently open.">FileOpenException</a></td><td>If the file is currently open. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00037">37</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;                                           {</div>
<div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;  <span class="keywordflow">if</span> (!<a class="code" href="classbadgerdb_1_1_file.html#a864d59b12302c26b14967bd1d3e520bd">exists</a>(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)) {</div>
<div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;    <span class="keywordflow">throw</span> FileNotFoundException(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>);</div>
<div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;  }</div>
<div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;  <span class="keywordflow">if</span> (<a class="code" href="classbadgerdb_1_1_file.html#a64836156a9bb5f81d2c2c4e6f3ada24d">isOpen</a>(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>)) {</div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;    <span class="keywordflow">throw</span> FileOpenException(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>);</div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;  }</div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;  std::remove(<a class="code" href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">filename</a>.c_str());</div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;}</div>
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<h2 class="memtitle"><span class="permalink"><a href="#a9a1b3cc43c4631bde58c1c4f670e1036">&#9670;&nbsp;</a></span>writePage()</h2>

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      <table class="memname">
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          <td class="memname">void badgerdb::File::writePage </td>
          <td>(</td>
          <td class="paramtype">const <a class="el" href="classbadgerdb_1_1_page.html">Page</a> &amp;&#160;</td>
          <td class="paramname"><em>new_page</em></td><td>)</td>
          <td></td>
        </tr>
      </table>
</div><div class="memdoc">
<p>Writes a page into the file, replacing any existing contents. The page must have been already allocated in this file by a call to <a class="el" href="classbadgerdb_1_1_file.html#a7d0e047bcc8dc4cee36aac5b2060bbe3">allocatePage()</a>.</p>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="classbadgerdb_1_1_file.html#a7d0e047bcc8dc4cee36aac5b2060bbe3">allocatePage()</a> </dd></dl>
<dl class="params"><dt>Parameters</dt><dd>
  <table class="params">
    <tr><td class="paramname">new_page</td><td><a class="el" href="classbadgerdb_1_1_page.html" title="Class which represents a fixed-size database page containing records.">Page</a> to write. </td></tr>
  </table>
  </dd>
</dl>

<p class="definition">Definition at line <a class="el" href="file_8cpp_source.html#l00169">169</a> of file <a class="el" href="file_8cpp_source.html">file.cpp</a>.</p>
<div class="fragment"><div class="line"><a name="l00169"></a><span class="lineno">  169</span>&#160;                                         {</div>
<div class="line"><a name="l00170"></a><span class="lineno">  170</span>&#160;  PageHeader header = readPageHeader(new_page.page_number());</div>
<div class="line"><a name="l00171"></a><span class="lineno">  171</span>&#160;  <span class="keywordflow">if</span> (header.current_page_number == <a class="code" href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">Page::INVALID_NUMBER</a>) {</div>
<div class="line"><a name="l00172"></a><span class="lineno">  172</span>&#160;    <span class="comment">// Page has been deleted since it was read.</span></div>
<div class="line"><a name="l00173"></a><span class="lineno">  173</span>&#160;    <span class="keywordflow">throw</span> InvalidPageException(new_page.page_number(), filename_);</div>
<div class="line"><a name="l00174"></a><span class="lineno">  174</span>&#160;  }</div>
<div class="line"><a name="l00175"></a><span class="lineno">  175</span>&#160;  <span class="comment">// Page on disk may have had its next page pointer updated since it was read;</span></div>
<div class="line"><a name="l00176"></a><span class="lineno">  176</span>&#160;  <span class="comment">// we don&#39;t modify that, but we do keep all the other modifications to the</span></div>
<div class="line"><a name="l00177"></a><span class="lineno">  177</span>&#160;  <span class="comment">// page header.</span></div>
<div class="line"><a name="l00178"></a><span class="lineno">  178</span>&#160;  <span class="keyword">const</span> <a class="code" href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">PageId</a> next_page_number = header.next_page_number;</div>
<div class="line"><a name="l00179"></a><span class="lineno">  179</span>&#160;  header = new_page.header_;</div>
<div class="line"><a name="l00180"></a><span class="lineno">  180</span>&#160;  header.next_page_number = next_page_number;</div>
<div class="line"><a name="l00181"></a><span class="lineno">  181</span>&#160;  <a class="code" href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">writePage</a>(new_page.page_number(), header, new_page);</div>
<div class="line"><a name="l00182"></a><span class="lineno">  182</span>&#160;}</div>
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</div>
</div>
<hr/>The documentation for this class was generated from the following files:<ul>
<li>/home/ubuntu/study/dbmslab/lab2/BufMgr/src/<a class="el" href="file_8h_source.html">file.h</a></li>
<li>/home/ubuntu/study/dbmslab/lab2/BufMgr/src/<a class="el" href="file_8cpp_source.html">file.cpp</a></li>
</ul>
</div><!-- contents -->
<div class="ttc" id="aclassbadgerdb_1_1_page_html_a785a1e756d47fb7f8f3603a3fe8ffcef"><div class="ttname"><a href="classbadgerdb_1_1_page.html#a785a1e756d47fb7f8f3603a3fe8ffcef">badgerdb::Page::INVALID_NUMBER</a></div><div class="ttdeci">static const PageId INVALID_NUMBER</div><div class="ttdef"><b>Definition:</b> <a href="page_8h_source.html#l00123">page.h:123</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a9a1b3cc43c4631bde58c1c4f670e1036"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a9a1b3cc43c4631bde58c1c4f670e1036">badgerdb::File::writePage</a></div><div class="ttdeci">void writePage(const Page &amp;new_page)</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00169">file.cpp:169</a></div></div>
<div class="ttc" id="anamespacebadgerdb_html_a1f49e404293bf4240756b89b53b1587a"><div class="ttname"><a href="namespacebadgerdb.html#a1f49e404293bf4240756b89b53b1587a">badgerdb::PageId</a></div><div class="ttdeci">std::uint32_t PageId</div><div class="ttdoc">Identifier for a page in a file.</div><div class="ttdef"><b>Definition:</b> <a href="types_8h_source.html#l00015">types.h:15</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a600baaf77d18f39e51ae7473eca633c4"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a600baaf77d18f39e51ae7473eca633c4">badgerdb::File::File</a></div><div class="ttdeci">File(const File &amp;other)</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00065">file.cpp:65</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_af16040a60f18c99305348077ac9e8aa8"><div class="ttname"><a href="classbadgerdb_1_1_file.html#af16040a60f18c99305348077ac9e8aa8">badgerdb::File::filename</a></div><div class="ttdeci">const std::string &amp; filename() const</div><div class="ttdef"><b>Definition:</b> <a href="file_8h_source.html#l00179">file.h:179</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a864d59b12302c26b14967bd1d3e520bd"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a864d59b12302c26b14967bd1d3e520bd">badgerdb::File::exists</a></div><div class="ttdeci">static bool exists(const std::string &amp;filename)</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00054">file.cpp:54</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a343b7fb1a238992f02454e9e81837acd"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a343b7fb1a238992f02454e9e81837acd">badgerdb::File::readPage</a></div><div class="ttdeci">Page readPage(const PageId page_number) const</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00149">file.cpp:149</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a64836156a9bb5f81d2c2c4e6f3ada24d"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a64836156a9bb5f81d2c2c4e6f3ada24d">badgerdb::File::isOpen</a></div><div class="ttdeci">static bool isOpen(const std::string &amp;filename)</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00047">file.cpp:47</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a32e94f392eb3740dd9eb9101b9e09d47"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a32e94f392eb3740dd9eb9101b9e09d47">badgerdb::File::begin</a></div><div class="ttdeci">FileIterator begin()</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00214">file.cpp:214</a></div></div>
<div class="ttc" id="aclassbadgerdb_1_1_file_html_a01e224676a67634f21d53fc4189b8f11"><div class="ttname"><a href="classbadgerdb_1_1_file.html#a01e224676a67634f21d53fc4189b8f11">badgerdb::File::end</a></div><div class="ttdeci">FileIterator end()</div><div class="ttdef"><b>Definition:</b> <a href="file_8cpp_source.html#l00219">file.cpp:219</a></div></div>
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